1) Field of the Invention
The present invention relates generally to high clearance crop sprayers, and more specifically to a narrow steerable front wheel assembly for such a vehicle.
2) Related Art
High clearance crop sprayers such as the John Deere Model 6000 Hi-Cycle typically have a frame supported a substantial distance above the ground by a single steerable front wheel located on the centerline of the vehicle and two rear wheels transversely spaced on opposite sides of the centerline. The wheels must be narrow to run between rows of crops and to avoid crop damage even in narrowly spaced rows of mature plants. In rough ground conditions, the sprayer is subjected to a considerable amount of bumping and vibration which results in extra fatigue for the operator and added wear and tear on the vehicle and the sprayer components. To reduce the impact of the ground conditions, the operator must slow the vehicle to a speed under the normal operating speed which results in lost productivity.
Some sprayers such as the Melroe Spra-Coup include a cushion narrow front to smooth the ride and lessen impact loading on rough ground surfaces. A single shock absorber is supported above the wheel with a large cushion spring encircling the shock absorber. A relatively massive yoke assembly extends upwardly adjacent the steering yoke to a connection with the lower ends of the spring and shock absorber. A substantial amount of space between the top of the wheel and the underside of the vehicle frame is required to accommodate the cushion front.